Fibroids During Pregnancy
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Fibroids are common benign (not malignant or cancerous) growths of fibrous tissue and muscle fibers often found in the uterus. Fibroids (also called leiomyomas,  fibromyomas,  and myomas) may be found in up to 4% of pregnancies  [1-5] . Fibroids vary in size from the size of a pea to more than eight inches (20 centimeters)  in diameter.

The types of uterine fibroids are named according to where they are found in the uterus:
  • Subserosal fibroid
    Under the lining of the uterine surface.
  • Intramural fibroids
    Within the uterine wall.
  • Submucosal fibroids
    Under the lining of the uterine cavity.
    Large submucosal fibroids have been associated with recurrent pregnancy loss[9].
  • Pedunculated
    The fibroid is connected to the uterus by a long stalk.
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Symptoms of fibroids may include:

  • Feeling of fullness or pressure in the lower abdomen.
  • Pelvic cramping or pain.
  • Frequent urination.
  • Constipation.
  • Sudden, severe pain may occur if a pedunculated fibroid twists on its stalk.
  • Heavy menstrual bleeding when not pregnant.
However, most often there are no symptoms associated with fibroids.

Can fibroids harm my baby?

Most studies have not found an increased rate of intrauterine growth restriction (IUGR) or of stillbirth (fetal demise) in pregnancies complicated by uterine fibroids [2,9]

Although there have been uncommon reports of limb abnormalities, head deformities, congenital torticollis (wryneck), and caudal dysplasia in the fetuses of pregnancies that were complicated by large uterine fibroids it is unclear whether these abnormalities were related to the presence of the uterine fibroid or an underlying maternal condition [6-8]

How might a fibroid affect my pregnancy?

Studies have most consistently shown pregnant women with fibroids to be at increased risk for pain, breech presentation, malposition, and cesarean delivery [9]. In at least one study the size of the fibroids was not significantly associated with an increased risk for cesarean delivery, and nearly 70% of women with fibroids 10 cm in diameter or larger were able to achieve  a vaginal delivery [10].

Some but not all studies have shown pregnant women with fibroids to be at increased risk for preterm birth, premature rupture of the membranes,postpartum hemorrhage, and placental abruption [9,10]. Submucosal , fibroids located beneath the placenta, and fibroids 7 to 8 cm in diameter had the highest risk for abruption in one study [2].

Studies have not consistently shown an association between uterine fibroids and placenta previa [9]

Less common complications that have been attributed to fibroids include acute renal failure,  urinary retention, disseminated intravascular coagulation, spontaneous hemoperitoneum, uterine inversion, and uterine incarceration, [ 14-17]


Can uterine fibroids  be treated during pregnancy?

Although removal of fibroids during pregnancy has been performed safely during the first and second trimesters of pregnancy removal of fibroids during pregnancy is usually reserved for women who have subserosal or pedunculated fibroids with pain that is unresponsive to rest, intravenous fluids, NSAIDs , and narcotic medications [2,9].


Will the fibroid grow?

Overall most uterine fibroids do not appear to change in size during pregnancy. Growth of fibroids seems most likely to occur during the first trimester in fibroids larger than 5 cm in diameter. Fibroids less than 5 cm in diameter tend to remain stable or decrease in size [9].


If I have a cesarean delivery can the doctor remove the fibroid at the time of the surgery?

Removal of fibroids (myomectomy) at the time of cesarean delivery has been associated with significant hemorrhage in some studies [2,9]. However, in experienced hands removal of easily reached subserosal or pedunculated fibroids may be a safe procedure [11-13].




1. Rice JP, Kay HH, Mahony BS. The clinical significance of uterine leiomyomas in pregnancy. Am J Obstet Gynecol 1989;160:12126.PMID: 2658611

2. Exacoustos C, Rosati P. Ultrasound diagnosis of uterine myomas and complications in pregnancy. Obstet Gynecol 1993;82:97101.PMID: 8515934

3. Katz VL, Dotters DJ, Droegemueller W. Complications of uterine leiomyomas in pregnancy. Obstet Gynecol 1989;73:5936.PMID 2927854

4. Burton CA, Grimes DA, March CM. Surgical management of leiomyomata during pregnancy. Obstet Gynecol 1989;74:7079.PMID 2812645

5. Hasan F, Arumugam K, Sivanesaratnam V. Uterine leiomyomata in pregnancy. Int J Gynaecol Obstet 1991;34:458.PMID 1671020

6. Matsunaga E., Shiota K.:Ectopic pregnancy and myoma uteri: teratogenic effects and maternal characteristics.Teratology. 1980;21:61-9.PMID:7385056

7. Graham J.M., Miller M.E., Stephan M.J., et al: Limb reduction anomalies and early in utero limb compression. J Pediatr;96. 1052-1056.1980; PMID 7373466

8. Romero R., Chervenak F.A., DeVore G.:  Fetal head deformation and congenital torticollis associated with uterine tumor.  Am J Obstet Gynecol 141. 839-840.1981; PMID 7198386

9.Ouyang DW eat al. ,Obstetric complications of fibroids.Obstet Gynecol Clin North Am. 2006;33:153-69. PMID: 16504813

10. Qidwai Obstetric outcomes in women with sonographically identified uterine leiomyomata. Obstet Gynecol. 2006 ;107:376-82.PMID: 16449127

11. Hassiakos D et al,. Myomectomy during cesarean section: a safe procedure? Ann N Y Acad Sci.2006 ;1092:408-13.PMID:17308166

12. Dimitrov A,et al. [Myomectomy during cesarean section] Akush Ginekol (Sofiia). 1999;38:7-9. PMID: 10730373

13. Kaymak O,et al. Myomectomy during cesarean section. Int J Gynaecol Obstet. 2005;89:90-3. PMID:15847868

14. Phelan J.P.:  Myomas and pregnancy. Obstet Gynecol Clin North Amer 22. 801-805.1995;  PMID:8786883

15. Monga AK, Woodhouse CR, Stanton SL:  Pregnancy and fibroids causing simultaneous urinary retention and ureteric obstruction.  Br J Urol 77. 606-607.1996; PMID: 8777631

16. Feusner A.H.,Mueller P.D.: Incarceration of a gravid fibroid uterus. Ann Emerg Med;30. 821-824.1997; PMID: 9398784

17. Courban D., Blank S., Harris M.A., et al:  Acute renal failure in the first trimester resulting from uterine leiomyomas.  Am J Obstet Gynecol 177. 472-473.1997;  PMID:9290476

Created 6/15/07
Updated 11/14/07



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